Ink jet printing is a well-known technique by which printing is accomplished without contact between the printing device and the substrate on which the printed characters are deposited. Briefly described, ink jet printing involves the technique of projecting a stream of ink droplets to a surface and controlling the direction of the stream so that the droplets are caused to form the desired printed image on that surface.
The technique of ink jet printing or non-contact printing is particularly well suited for application of characters onto irregularly shaped surfaces, including, for example, glass, metal, or plastic containers, generally used for holding beverage, cosmetic, pharmaceutical, liquor, and health care products.
In general, an ink jet ink composition should meet certain requirements to be useful in ink jet printing operations. These relate to viscosity and resistivity of the ink, the solubility and compatibility of the components, and/or the wettability of the substrate. Further, the ink should be quick drying and smear resistant, and be capable of passing through the ink jet nozzle(s) without clogging, and permit rapid cleanup of the machine components with minimum effort. The printed message or image should also resist abrasion and in some cases mild solvents.
Certain substrates such as glass and metal present challenges to ink jet printing. The quality of some of the attempted ink jet ink compositions is such that there is a need to improve one or more properties such as moisture penetration, adhesion, isopropanol splash resistance, and ice bucket rub resistance. Certain ink jet ink compositions also cause ink buildup on the printer nozzle plate, thereby requiring frequent clean up and maintenance.
Thus, there exists a need for an ink jet ink composition for printing on glass and metal substrates having improved performance characteristics, such as reduced ink buildup on the printer nozzle plate and solvent resistance, ice bucket rub resistance, and rub resistance of the printed images.
The invention provides such a composition. The advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.